Means operated by a starter generator for cooling a gas engine



July 12, 1949. F. M. JONES 2,475,843

MEANS OPERATED BY STARTER GENERATORS FOR COOLING GAS ENGINES OriginalFiled Oct. 26', 1944 3 Sheets-Sheetl INVENTOR. FREDERICK M JOES y 1949-F. M. JONES 2,475,843

MEANS OPERATED BY STARTER GENERATORS FOR COOLING GAS ENGINES OriginalFiled Oct. 26, 1944 3 Sheets-Sheet 2 JNVENTOR. FRED RICK M. JONES FIG.3. my

' ATTORNEY July 12, 1949. F. M. JONES MEANS OPERATED BY STARTERGENERATORS FOR COOLING GAS ENGINES Original Filed 001:. 26, 1944 3Sheets-Sheet 3 INVENTOR. FFE E M. JONES Y/ w h/ 5 ATTO RNE1 PatentedJuly 12, 1949 UNITED STATES PATENT OFFICE MEANS OPERATED BY A STARTERGENERA- TOR FOR COOLING A GAS ENGINE nesota Original application October26,

6 Claims. 1

My invention relates to means operated by a starter generator forcooling it and a gas engine, and has for its object to provide incombination a starter generator directly attached to the front of thegas engine and operatively connected with the motor shaft thereof,wherein the armature is caused to rotate in relation to the fieldmembers, together with means operatively connected with said armature inconjunction with air passages extending past the rotating armature andabout the cylinder or cylinders of thegas engine to effect the coolingthereof,

The usual practice heretofore has been to rotate the armature within themagnetic field. That is, to have the windings and poles of the magneticfield stationary and external to the armature and to rotate the armaturein the form of a laminated cylinder within the field coils and windingspositioned as in a hollow shell. This has necessitated objectionablewide spacing of the pole pieces and rotating the armature at such highspeed that even though the commutator is reduced in diameter, the actualfiow of current impulses thereto and therethrough 1s less than would beexpected. Furthermore, the small size of the armature necessary withinthe members of the magnetic field makes it rather ineffective as aninertia fly-wheel.

I have discovered that an arrangement of the field poles and windings inthe form of a cylinder of relatively small diameter held stationary atthe center of a generator and of the armature in the form of a hollowshell which rotates with its connected commutator about the field polesand field windings, produces a much more efficient generator of electriccurrent generated or required for the starter and one which may functionas a perfectly combined inertial fiywheel and blower positioned directlyupon the gas engine motor shaft so at the same time to provide therequired inertia power to absorb the inertia losses from reversals ofmovement of the gas engine pistons and to produce a strong current ofair to pass over and among the radiator fins of an air-cooled gas engineand thus to cool the same. I also discovered that this air current hasthe important ffect of cooling the enerator itself and thus preservingthe insulation.

It is a principal object of my invention, therefore, to arrange thefield poles and windings of a generator in the form of a cylinder heldstationary at the center of a generator with an opening through thecenter thereof for the reception of an extension of the gas engine motorshaft andto arrange the armature in the form 1944, Serial No.

Divided and this application October Serial No. 621,341

of a hollow shell directly connected to the motor shaft and rotated byit about the field poles and windings, and to use the rotating armatureas a means for operating blower means to cool the gas engine and thegenerator.

It is a further object of my invention to form upon the outer peripheryof the armature framework a circumferentially arranged series of blowerfan blades, and to arrange them withina shroud about air coolingradiator fins on the motor cylinder, so the operation of the generatoritself will cause currents of air to move within the shroud and throughthe radiator fins and about all parts of the generator to cool it andthe motor.

It is a further object of my invention to so position the generator inrelation to the shroud that the blower blades operated by the rotatingarmature will be positioned to rotate centrally as to a multiplecylinder gas engine, as for example a two-cylinder gas engine, and theair currents generated by said fan blades will be distributed under theshroud so as to pass under and about the radiator fins on both saidcylinders and discharge with the heat removed vertically upward.

A further object of the invention is to provide a multiple purposemachine which includes an engine of air cooled type having its drivenshaft extending from opposite sides of the engine with a power take-offconnected to one end of the shaft and a starter generator connected tothe other end of the shaft for starting the engine and thereafter tobecome an electric power plant, together with means operated by thestarter generator for cooling the engine.

The full objects and advantages of my invention will be pointed out indetail and the different relationships of the parts will be clearlyindicated in the following specification, and the novel featuresindividually in making up new combinations and such combinations bywhich the aforementioned advantageous results are secured, will beparticularly pointed out in their cooperating arrangement in theappended claims.

This application is a division of my pending application, Serial No.560,454, filed October 26, 1944.

In the drawings illustrating an application of my invention in one ofits forms:

Fig. 1 is a front elevation view of my armature blower mechanism as itwould appear in position assembled upon the front end of a crankshaft ofa gas engine with the shroud and motor parts omitted.

acrasas 1'18. 2 is a rear elevation view of an entire twocylinder motorassemblage similar to the showing of Fig. 1 and showing the relation ofall of the rts. Fig. 3 is a longitudinal sectional elevation view of thestarter generator and the fan blades attached to the rotating armaturetaken on line 3-3 of Fi 1.

Fig. 4 is a side elevation view of the engine and starter generatorassembly with some parts broken away and others shown in section.

Fig. 5 is a side elevation view on. a reduced scale of a gas enginehaving my generator and blower mechanism attached thereto with someparts broken away.

Fig. 6 is a top plan view of a two-cylinder gas engine showing thearrangement of the shroud as to both said cylinders and the top openingsfor escape of air after it has passed about the fins of said cylindersof the gas engine.

A base plate 10, Figs. 3 and 5, is shown bolted directly to the face ofa two-cylinder gas engine I i. To this base plate is secured by amultiplicity of bolts i3, as shown in Fig. 3, a pole piece designatedgenerally by the numeral l4. The bolts i3 have their heads l5countersunk in the outer face of the pole piece l4 and are screwed intointernally threaded bosses l6, Fig. 3.

The baseplate i0 is circular in outline and is formed with an outwardlyturned boss 1! which surrounds a bearing (not shown) that extends into acentral circular opening l8 through the base plate 10. A correspondingopening is is formed in the pole piece 14. The pole piece is providedwith an annular groove 26 forming a lip 2i which overlies the inner edge22 of the boss l1, and is spaced a suitable distance therefrom. Thefield windings 23, of known arrangement, are contained in annularchannels 24 formed in the mass of the pole piece, as indicated in Fig.3. The pole piece M has its outer portions fall in a cylindrical surface25.

The engine shaft l2 extends through opening i8 and has a portion 2'! inthe form of the frustum of a cone, with a cylindrical threadedextension, indicated in dotted lines in Fig. 3 at 28. Upon this conicalextension 21 of shaft l2 there is adapted to seat an internal conicalopening 29 corresponding in size and shape with the conical frustum 21,formed in a tubular frame extension 33 of a frame plate or head 36.

The extension 33 is formed with an annular ledge 30. The ledge 30 isengaged by the lower edge iii of a nut 32 threaded upon the threadedextension 28 by which the tubular member 33 has its conical seat 29forced upon the conical portion 21 of shaft i2. A pair of splinesindicated in dotted lines at 35, Fig. 3, firmly holds tubular extension33 for rotation with shaft i2. The nut 32 is countersunk at 36 into theopening leading through tubular extension 33. The nut is locked againstturning by a washer 3! and a lock ring 38 snapped into an internalgroove 33a formed in the inner body of tubular extension 33, Fig. 3.

The frame or head 34 is formed with an annular flange 39 having asloping outer wall 40. To the flange 39 is secured b a multiplicity ofscrew bolts 4| a blower ring 42 and an armature designated generally bythe numeral 43. The commutator 44 is a tubular member of standardconstruction which is held by being placed on the extension member 33 ofhead plate 34, and is additionally held thereto by screws, one of whichis shown at 45 in Fig. 3,'and which i. 4 are countersunk in the headplate 34, and which extend into segments insulated from the contact bodyof the commutator.

The windings of the armature and of the insulation, as shown, are ofstandard construction and need not be described in this application.

The frame head 34 is thus held for rotation with and .by the shaft l2.Hence, the armature 43 is firmly held tQ'IOtflte about the several polepieces 24 and the commutator is held to rotate with the armature. Thisis also true of the blower ring 42 which is held to the armature by thebolts 4| and rotates with it.

Upon the blower ring 42 is secured a multiplicity of curved blower vanes43, extending radially about the shaft 12, as shown in Figs. 1, 3. 4 and5. The vanes are also shown in dotted lines in Fig. 2 and in relation tothe enclosing shroud in Figs. 4 and 6. The vanes 43 are thus held forrotation with the blower ring 42 and the armature and connected parts.

My invention is shown applied to a two cylinder gas engine having a pairof opposed cylinders 41, 48. The crankshaft I2 extends through the frontand rear facesof the engine as shown in Figs. 2, 4, and 5. On the rearof the engine as it is normally used, a power transmitting means in theform here shown is a pulley 33 secured to the rear end of crankshaft i2for driving any form of a main load for which the engine is intended.The starter generator discussed in detail heretofore is mounted on whatmay be regarded as the front of the engine as it is normally used, andits operative portions are connected to the front end of the crankshaft12 as shown in Fig. 3. This arrangement affords two distinct advantages.Primarily the starter generator is used initiallyto crank the engine andthereafter is used to generate electric power which may be stored in abattery that supplies the source of power for the starting operation, orthe current may be used in any one of a number of other ways, such aspower for the ignition of the fuel. Secondly, its rotatable portions actas a flywheel to stabilize the operation of the crankshaft, and also tocounterbalance the torque of the main load which is connected to theother end of the crankshaft. Thirdly, by being positioned on the end ofthe crankshaft opposite the main load driving means, the overalldimensions of the engine and starter generator are materially reduced.This arrangement minimizes bearing wear and the use of elongatedbearings as in the instance where the starter generator was positionedon the same side of the engine as the power transmitting means andbetween said means and the engine, which was the prior art constructionof machines of this type. Furthermore, the blower vanes 46 by beingmounted on the periphery of the starter generator form a highlyeffective means of supplying a large volume of air for cooling the engme.

It follows that in order to carry the air to these two cylinders forcooling them a shroud should be so formed as to provide a chamber openat its outer end and otherwise enclosing and surrounding the blowervanes, and which encloses the two engine cylinders and will lead the airto move about the cooling fins on the engine cylinders and to dischargeto atmosphere through separate openings over each cylinder.

This shroud is designated generally by the numeral 49. It comprises aroughly oval-shaped casing 50 secured to the engine frame by bolts Thiscasing is formed at its front with a flaring. lip 52 surrounding acircular opening 53 which immediately surrounds the blower ring 42 andblades 46, being spaced 3. sufllcient distance from the edges of theblades at their closest points to the shroud portions 50 to preventcontact between the blades and the shroud, as shown in Fig. 4.

From the opening 53'the shroud has a portion 54 which spreads to thesides of the engine cylinders 41 and 48 and forms a chamber 55 whichopens into a passageway 59 underlying at each side the engine cylinders41 and 48.

The engine cylinders are provided with a multiplicity of heat-radiatingfins 56 which extend entirely around the cylinders and whichadvantageously are curved, as indicated at 51 in Figs. 4 and 5. In thetop of the shroud is .an opening at each sid above the respective enginecylinders 4'1 and 48, as indicated at 58 in Fig. 6.

In operation the starter generator has a primary function of startingthe engine, and thereafter it becomes operative to generate electricpower which is used to ignite fuel burned in the engine, and also tocharge a battery (not shown) which is used to supply power for thestarting operation. The circuit by which th electric current is conveyedfor these purposes is disclosed in Numero and Jones Patent 2,337,164,dated December 21, 1943, and assigned to the assignee of thisapplication. After the engine has been started and is self-operating,the starter generator becomes in addition to a source of electric power,an inertia flywheel to stabilize the operation of th engine crankshaftand also to counter-balance the main load being driven by the powertransmitting means 60. By being positioned on an opposite side of theengine from the power transmitting means (ill, the over-all dimensionsof the machine are materially reduced and other troublesome features areminimized. This is important, because in the prior art starter throughthe metal elements to the several vanes making up the blower and sincethese vanes are brought into contact with the large volume of airtravelling through the shroud, the vanes will transfer the heat of thegenerator to the air column.

The advantages of my invention are clearly apparent from the descriptionin the foregoing specification. With little consumption of power overthat normally employed to rotate the armature and commutator anexceptionally eflicient blower which is relatively large in diameteroperates to pass air in large volumes about and between ,the coolingvanes on a two-cycle gas engine.

The fan or blower is devoid of operating connections. It is simply anouter adjunct of the armature inertia flywheel, and because of itsgenerators such as is disclosed in Patent 2,33'7,-

164, the starter generator and the power takeofi are on the same end ofthe engine, and in addition to making a. longer structure as measuredalong the axis of the crankshaft, also tended to create an unbalancedcondition on the outer end of the driven shaft which carried both thepower take-off and the starter generator, and caused considerablebearing difliculties. Furthermore, in the arrangement forming thepresent invention, the starter generator carries the blower vanes 46,which are effective as a means of cooling the engine, where the same isof aircooled type. By virtue of the fact that the starter generator issecured to the front end of the engine, as distinguished from the rearend where the power take-off is located, it is capable of delivering airin a short unobstructed path to the engine and is therefore an improvedmeans of cooling the engine.

One of the principal advantages of the present invention resides in itscompactness which enables it to be mounted within a device where spaceis extremely limited. The dimensions of the combined engine andgenerator when taken along the axis of shaft I2 is about one-third ofthe dimension when taken on a plane transverse to the axis of the shaftwhen the shroud is included.

Another advantage resides in the manner of dissipating the heat createdin the generator. As most of the heat comes from the armature it will benoted that this heat may be conducted diameter, large relative to thesize of the gas engine cylinders, the large volume of air is not onlyeasily gathered and forwarded, but it is distributed over the armatureand commutator and about the gas engine cylinders and the cooling finsthereon with not only exceptionally large heat exchange contact, butalso with remarkable uniformity both in that contact and in theoperative effect of taking the heat from the engine.

A particularly'useful advantage comes from the fact that the largevolume of air introduced by the fan arrangement flows about thegenerator itself and all parts thereof. This effects in a remarkabledegree a. cooling of the generator itself and all of its parts andparticularly the insulation, which in present practice often is injuredor destroyed by excessive heat.

Iclaim:

1. In combination with an air-cooled engine and its main driving shaft,a flat base plate adapted to be bolted directly to the face of theengine, said plate having a central opening closely surrounding thedriving shaft, .a cylindrical field pole piece rigidly secured on oneside to the base plate, said pole piece having a central opening formingan extension of the opening in the base plate into which the end of thedriving shaft extends, a flat outer plate member parallel with the baseplate and having a circular flange turned inwardly at its outer edges tosurround the pole piece and forming an enclosure on the side of the polepiece opposite the engine, an armature rigidly bolted within theinterior of said member for rotation with respect to the pole piece,fastening means passing through the outer surface of said'member at acentral portion thereof for securing said member to the outer end of thedriving shaft whereby said member and its connected armature rotate inunison with the driving shaft, a plurality of curved vanes mounted oneach quadrant section of the outer surface of the flanged portion ofsaid member, said vanes being adapted to direct the flow of a large bodyof air in the direction of the engine when said plate member is rotated,and a shroud which closely encloses the engine and the generator andforms an air channel to and about the engine, said shroud having a firstopening in alignment with the outer side of the plate member foradmitting air into the shroud and in contact with the vanes, said shroudhaving a second opening over the top of the engine for egress of airafter the same has been in contact with the engine.

2. In combination with an air-cooled engine and its main driving shaft,a threaded connecting portion at the outer end of said shaft, 3

s am starter generator comprising a field pole piece of circular outlinehaving a plurality of field windings adjacent its periphery, means forrigidly securing said pole piece directly on one face of the engine,said pole piece having a central opening into which the outer end of thedriving shaft extends, a fiat outer plate member having a circularflange turned inwardly at its outer edges to surround the pole piece andforming an enclosure on the side of the pole piece opposite the engine,an armature rigidly bolted within the interior of said member forrotation with respect to the pole piece, said outer plate member havinga central opening in alignment with the end of the driving shaft, athreaded connector adapted for entry through the opening in said platemember for securing said member to the outer end of the driving shaft insuch a manner that the plate member rotates in unison with the drivingshaft, a plurality of arcuately shaped vanes mounted on each quadrantsection of the outer surface of the flange portion of said member, saidvanes being adapted to direct the fiow of a large body of air in thedirection of the engine when said plate member is rotated, and a shroudwhich closely encloses the engine and the generator and forms an airchannel extending to and about the engine for directing air into contactwith said vanes and directing the air delivered by said vanes intocontact with the engine.

3. In combination with an air-cooled engine having a, driven shaft, aflat plate member adapted to be bolted directly to a face of the engine,said plate member having a central opening closely surrounding thedriven shaft, a cylindrical pole piece rigidly secured on one lateralsurface to said plate member in such a manner as to render the polepiece stationary, said pole piece having an opening extending throughits central axis to provide entry for said driven shaft, a fiat circularplate member positioned on the opposite lateral side of the pole pieceand forming an enclosure about the side of the pole piece opposite theengine and parallel to the first named plate member, said second namedplate member having a central tubular projection which extends into thecentral opening of the pole piece and surrounds the outer end of thedriven shaft, said projection having an opening therein, said platemember having an inwardly extending peripheral flange surrounding theouter limits of the pole piece, an armature carried on the peripheralflange and surrounding the pole piece, a connector for, entry throughthe opening in the central projection for securing said plate member tothe outer end of the driven shaft in such a manner that the plate memberrotates in unison with the driven shaft, a plurality of arcuately shapedvanes mounted on each quadrant section of said flange, and a shroudwhich closely encloses the engine and the vanes, said shroud having afirst opening in alignment with the outer side of the second named platemember for admitting air into the shroud and in contact with said vanes,said shroud having a second opening over the top of the engine foregress of air after the same has been in contact with the engine.

4. A compact multiple purpose machine, including in combination, anengine of air-cooled type, a crankshaft within said engine and havingits opposite ends extending outwardly from opposite sides of the engine,power transmitting means connecting with a first end of the crank- I 8shaft and at the rear of the engine and adapted to drive a load, a fiatplate adapted to be bolted to the front face of the engine, a startergenerator positioned on the front of the engine for initially startingthe engine and generating elecabout the engine, and a series of fanblades positioned within the shroud and extending about the periphery ofthe starter generator for drawing air into the shroud and blowing thesame over the engine when the latter is self-operating, said fan bladesand the rotatable portion of the starter generator being conjointlyconnected to the second end of said crankshaft and forming a unitaryinertia element for stabilizing the crankshaft and counter-balancing theload on the first end of the crankshaft.

5. A compact multiple purpose machine, including in combination, anengine of air-cooled type, a crankshaft within said engine and havingits opposite ends extending outwardly from opposite sides of the engine,power transmitting means connected to a first end of said crankshaft andadapted to drive a main load, a flat annular member secured to theopposite side of the engine, a starter generator positioned on theopposite side of the engine from the power transmitting means forinitially starting the engine and generating electric power when theengine is self-operating, said starter generator comprising a stationaryfield pole piece and a rotatable armature, fastening means for securingthe field pole piece to the outer surface of the fiat annular member, asecond fiat annular member having a peripheral flange which extendsbeyond the outer limits of the pole piece and forms an outer enclosureabout the pole piece on-the side opposite the engine, a multi plicity ofvanes secured to the peripheral flange of said second member, fasteningmeans for securing the armature within the interior of said secondmember for rotation with respect to the pole piece, fastening means forsecuring said second member to the second end of the crankshaft wherebysaid second member and the armature form an inertia flywheel tostabilize the crankshaft and counter-balance the load on the first endof the crankshaft, and a shroud for surrounding the vanes on said secondmember and forming an air channel for directing air in and about theengine to cool the same when the engine is driving said second member.

6. A compact multiple purpose machine, including in combination, anengine of air-cooled type, a crankshaft within said engine and havingits opposite ends extending outwardly on either side of the engine,power transmitting means connected to a first end of said shaft andadapted to drive a main load, a starter generator positioned on theopposite side of the engine from the power transmitting means andadapted to initially start the engine and thereafter to generateelectric power when the. engine is selfoperating, said starter generatorcomprising a stationary portion and a rotatable portion, and a series offan blades extending about the periphery of the starter generator forblowing air over the engine to cool the same when the engine isself-operating, said fan blades and the rotatable portion of the startergenerator being con- FREDERICK M. JONES.

REFERENfiES CITED The following referenlces are of record m the file ofthis patent:

UNITED STATES PATENTS Number Re. 23,000 979,003

Name Date Jones May 11, 1948 Heany Dec. 20, 1910 Number 10 Name DateHeany Nov. 17, 1914 Hassler Feb. 15, 1916 Kouyoumjian Mar. 29, 1917Kouyoumjian Mar. 20, 1917 Andrews et; a1. Mar. 6, 1923 Burchett Jan. 13,1925 Andrews et a1. Nov. 23, 1926 Tingley Nov, 28, 1933 Chilton Feb. 27,1934 Heintz May 15, 1934 Else Sept. 8, 1936 Ballen'tine Feb. 23, 1937Sutherland July 30, 1940

